either of these aspects singly, but must find room for both--for both
prayer and sacrifice. They cannot be mutually exclusive, nor can they
be simply juxtaposed, as though they were atoms unrelated to one
another, accidental neighbours in the same district. There must be a
higher unity, not created by or subsequent to the coalescence of
elements originally independent of each other, but a higher unity of
which both prayer and sacrifice are manifestations. This higher unity, I
venture to suggest, is the first principle of religion; and, if it is
not explicitly recognized as the first principle of religion either by
Robertson Smith or by Frazer, that may well be because their attention
is concentrated on the earlier stages in the evolution of religion, when
as yet it is not conspicuous and is, therefore, though in fact
operative, liable to be overlooked. As Ferrier has said, 'first
principles of every kind have their influence, and indeed operate
largely and powerfully long before they come to the surface of human
thought and are articulately expounded.' What then is the first
principle of religion which only after long ages of evolution rose to
the surface of human thought, and which, though it had been operative
largely and powerfully, came only in the slow course of human evolution
to be articulately expounded? The first principle of religion is
love--love of one's neighbour and one's God.

In the light of that first principle it is manifest that prayer and
sacrifice are not fundamentally unrelated and accidentally juxtaposed: a
sacrifice accompanied not even by unspoken prayer, prompted by no
desire, no wish for anything whatever, is a meaningless concept. Equally
unmeaning and unintelligible is the idea of a prayer which involves no
sacrifice--whether by sacrifice we understand the offering of gifts or
the sacrifice of self. But perhaps it may be said that, even though love
alone can lead to sacrifice of self, still it is undeniable that prayers